


i forgot what it feels like to regret my sins

by orphan_account



Category: Undertale (Video Game)
Genre: Other, Pet Names, Plot What Plot/Porn Without Plot, Praise Kink, Public Sex, True Pacifist Timeline implied
Language: English
Status: Completed
Published: 2015-10-31
Updated: 2015-10-31
Packaged: 2018-04-29 02:13:29
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,858
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5112521
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: <blockquote class="userstuff">
              <p>“That what get you off, sweetheart?” Your breath hitches at the sudden change of tone in Sans’ voice. He crowds you against the alley wall and looks up into your eyes. “I don’t think you know what you’re dealing with.”</p>
<p>“Oh? Don’t I?” You say, braver than you feel.</p>
            </blockquote>





	i forgot what it feels like to regret my sins

**Author's Note:**

> Holyshitdon'tlookatme. At least I kept the promise to myself that my first fic for UT wouldn't be NSFW? Reader is supposed to be read as in-place-of Frisk ie made it through all the stuff that in-game Frisk did, Frisk didn't appear, but they're NOT Frisk. No pronouns are used but boobs/vagina/etc. are featured. God. I'll write something better next time. For now, here's 3k words of self-indulgent nonsense.

As you watch Sans walk away across the plush carpeted floor of Hotel MTT, your thoughts are troubled. The room feels chilly, but your face is warm and your thighs are sticking together with sweat. Your phone buzzes feebly in your pocket- probably Alphys again, impatient at your many detours. Sans’ voice echoes in your mind, one part concern and one part danger. _Is what you have to do, really that important?_

You’re not sure anymore.

Part of it probably has to do with the current _problem_ you’re having, but certainly you’re not going to let that keep you here? Not when you wanted so badly to go home, right?

If only it were just that. Sure, you’re a little turned on ( _Sans’ voice had dipped low, perhaps for the environment or perhaps just for added effect to the threat slipping from his mouth. You’d swallowed and squirmed in your seat._ ) but… Sans in general makes you want to stay. Then there’s Papyrus, and Undyne, and maybe even Alphys. And there’s… Well, you think of a chair, large enough for two in front of a toasty fire. You think of a comfy bed and home cooked meals. (More than you’d ever had Above.) You think of Grillby’s, grease on your fingertips and food growing cold as you laugh at _who’s_ jokes? There’s a bed with your name on it at Toriel’s, a couch ready for you to crash on at Sans and Papyrus’, and Undyne needs help restoring her house, right? Alphys, more than ever, could use an extra friend, right?

You have yourself ninety-percent convinced when you remember that they all want to leave, too. So you follow your gut instinct.

Although mulling over your thoughts had given Sans a head start, you manage to catch him by the back of his sweater at the edge of the alleyway. His hand is suddenly there, wrapped tight around your wrist and he’s turning with this _look_ in his eyes- it feels like a manifestation of the kind of mood that had you writhing in your seat earlier- before it falls and his fingers loosen.

“The core’s the other way, kid.” He grunts. Your face, screwed up in determination, falls for a second. You press onwards with your intentions before you can lose your nerve.

“Do you want me to go?” You blurt.

“What?” His pupils flare up and dip, his tone turns suspicious. He removes his hand from your arm completely and tucks it gingerly back into his pocket. You try not to feel disappointed.

“Back to the surface- do you want me to?”

“That’s not really up to me, now, is it?” You should have expected him to be circularly argumentative.

“In the beginning… you didn’t want me to. Right? So what about now?” You watch his eyes, pinpricks of light for pupils surprisingly adept at expressing emotion. He seems… bewildered, if you’ve learned to read him properly. Awkward and scared at your questioning.

“It’s… not my place to stop you. You want- _wanted_ , to-” He tries, again, to avoid the question.

“Sans.” He looks up at you. You fold your arms and then unfold them. “Do _you_ want me to go?”

He seems to really think about his answer. “…No.” You can feel the way your own face physically lights up at the answer.

“Then I’m not going.” You take a step towards him. He stays in place but tilts his head.

“What?”

“I want to stay. If you want me to. If you want me.” You take another half-step and his whole body tenses up, his eyes seeming to flare in recognition of your words. An awkward laugh escapes him. Oh, _no_.

“Uh,”  
“I mean um,” You both begin, then fall quiet.

“You-”  
“I’ll just-” You pause again and look at the ground, face burning and stomach churning.

You jump a little when his hand returns to your wrist, a lighter pressure this time around. “Are you sure you know what signals yer sending?”

A laugh leaves you, kind of like a yelp. “Me? What about _you_?”

“What?” He seems genuinely confused, _again_ , and you wonder how many times one person can stuff their foot into their mouth.

“Oh. Well, that’s, um…” His eyes narrow and his perpetual grin gets… predatory. His hands tighten on your wrist; nothing like before, but gripping, solidly there. You blush and turn your face away. “At the table.” You mumble.

He laughs, low and so him but _so not_.

“That what get you off, sweetheart?” Your breath hitches at the sudden change of tone in Sans’ voice. He crowds you against the alley wall and looks up into your eyes. “I don’t think you know what you’re dealing with.”

“Oh? Don’t I?” You say, braver than you feel.

There’s a sudden mad scramble, hands slipping into unfamiliar territory. His metacarpals pinch at the thin skin of your wrist and you tug on his hood, upwards. It’s not a kiss like you’d usually have it, but it’s a kiss nonetheless. (There’s lip to teeth action so it’s a _kiss_ dammit.) You have the upper hand- you _should_ have the upper hand- but he presses you against the wall like you’re made of nothing.

“No, you really don’t.” His voice is low next to your ear, sending a shiver rocketing down your spine. You twist your fingers in the soft, wooly lining of his sweater. With the hand not wrapped around your wrist like a vice, he touches your hip gently. You jolt and he chuckles. Heat floods your face. “Scared?”

“No.” Your voice comes out of you in a whisper. He drags the hem of your shirt up, thumb trailing over the thin, sensitive skin of your love handle and side.

“Don’t lie.” He tuts. Sans digs his thumb in, just under the wire of your bra. A noise escapes you, somewhere between a gas and a whimper. Your legs are shaking already.

Admittedly, you’ve been wound up since he’d threatened you at the table. _You’d be dead where you stand_. As if that hadn’t been the most terrifying yet confusingly arousing moment of your life, here you are with his hands all over you and his voice a dangerous promise at the shell of your ear. Of course you’re already wet.

“Seems’t’me you like being scared.” He punctuates this sentence with a nip to your ear and you can’t help but moan, shaky as it is.

“Oh, fuck.” You hiss on the tail end of it. Sans releases your wrist and pushes your shirt up entirely, leaning back to look at you. You wonder how you look, exactly; the sexy kind of flushed and disheveled or just a mess? He seems to like what he sees, though. He thumbs at the underwire edge of your bra. Every time he touches you, it makes your skin tingle. He slips his thumb up under the edge on either side and pulls it up; it pinches a bit but your breasts fall free and his grin grows absolutely devilish.

“Cute.” He murmurs. Somewhere between your offense ( _Hot! I’m smoking hot! Not cute!_ ) and your growing lust, you remember where you are.

“Sans, wait, shit, we’re _outside_!” You reach up and try to tug your bra back down but the swell of your chest prevents you from doing so easily.

He swats your hands out of the way. “That’s part of the danger, sweetheart.” The pet name practically has you dripping, and you freeze with your hands curled up beside your chest. He cups a breast in one hand, swiping his thumb over a nipple. You squirm and your breath hitches. “Sans.” You breathe out, wheedling. He pays you no mind.

“So tell me, what exactly did it?” His left hand falls to your hip and he tugs you towards him. You leave the safety of the brick wall, something solid to press away and into and instead fall into him. He nuzzles along your jaw and his breath ghosts along the shell of your ear. You shudder, and he squeezes your breast.

“Answer me.” The squeeze turns rough and you writhe. Your voice is rough when you answer, “The story you told me, at the end.”

“That’s chilling, kid. Real freaky.” He pulls his hand away from your hip, and you tremble when you feel his fingertips lightly press to the front of your shorts. “S’real fucked up. And it got you going this bad?”

“ _Sans_.”

“Yes?” He pulls back and looks at you, so innocently. You’re quivering, sweating again, and a misstep from moaning at any second. “I said, _yes_?” He presses his fingers against you harder and a groan rips out of you. You steady yourself against him, hands on his shoulders, and you tuck your face close against his neck. Your face is hot and your voice is low and you curl into him to hide when you speak.

“Wan’ you.” Your voice cracks. Sans makes a pleased, low moan into your ear and presses you bodily against the wall.

“If you insist.” He pulls your shorts down, your underwear tangled in the mix. When they get loose enough you let them fall past your knees, and you part your thighs just a bit when the constricting material is out of the way. Sans moves his hand back to roughly cup your sex, and his other rounds your hips to grope at your ass. A cold, hard finger parts your folds and you whimper piteously.

“Weren’t you th’one who was just sayin’ we’re outside?” He twists his wrist. “Now you’re beggin’ for it. Tsk.” You’re too busy rutting against his fingers to give him any sort of answer. He seems willing to let it slide, this time. Sans words a second finger into you and rubs along your inner walls with slow purpose. You can feel how wet you’re getting against the curve of his hand pressed against your clit and the stickiness between your thighs. When he wedges a third finger inside you, you gasp and grind down harder. They slip further in and a loud moan escapes you.

“Better quiet down, sweetheart.” He squeezes your ass in warning. “Wouldn’t want us getting caught.” You bite your lip and nod, but it’s damn hard when he’s finger fucking you slow and hard. You’re the wettest you’ve ever been and you want something so much thicker and warmer in place of his fingers.

He finds your spot and seems to love the tortured squeal you let out when he presses against it too hard. “That good?”

“Sans, _please_.”

“Please what?” He curls his fingers and rubs just-so. Your thighs tremble; your knees threaten to buckle. You moan weakly and grin at his sweater, afraid you’re going to fall down. He does it again, harder and his voice is practically a growl. “Please _what_?”

“ _Fuck_ me!” You warble, arching up to your tip toes to get away from the delicious pleasure of his fingers against your spot. It’s both an exclamation and a plea. He pinches your ass and you squeak.

“I know you can’t-” You babble, more than pleased with his fingers, mortified-

“What? Of course I can.” He drags his fingers out of you and pulls your leg up around his waist. “You severely underestimate me, kid.”

There’s a thick, warm presence against your mound and you jump for a third time, looking down. “Oh my god.” You whisper. A laugh sneaks out before you can help it. It’s _blue_ for chrissakes.

“That’s not very nice.” He grumbles. Sans reaches with his free hand and roughly grabs at your chin. You regret the laugh nearly instantly as your eyes meet; his left eye is burning blue and bright and you shiver. “Seems I gotta teach y’some manners, hm?” He thumbs at your bottom lip and you hold your breath. He leans in, mouth nuzzling against yours in semblance of a kiss.

“Why don’t you ask for what you want, _nicely_?” Your breath shudders out of you and you nod, leaning your head into his touch. The heavy promise of his cock against your folds has made you a lot more eager to follow his instructions.

Your voice still shakes when you quietly plead, “I want you to fuck me, please, Sans.” He smiles- it’s smaller than his normal grin, more private and intimate, a _promise_.

“Try again, sweetheart.” You whimper a little and wiggle your hips closer to his. “Sans, _Sans-_ ” Desperation washes over you; it’s foreign and new and you’re drunk on it. Your breath hitches and your voice turns reedy. “Fuck me hard, Sans, please give it to me, oh _please._ ” You think you’re about to cry when he takes mercy on you.

“Y’got it, kid.” He hefts your thigh higher and reaches down to position his dick right at your entrance, tip pressing into your folds quick and smooth with how wet you are. You hiccup on a noise and try to relax; he’s wider in the middle and you make little gasping noises, voice undulant as he presses in inch by inch.

“Shit.” He breathes. Privately, you agree.

He sets a pace almost immediately, shallow thrusts that nudge against the deepest part of you in the best way. A sob falls from your lips. He’s moved his hand back to cupping your face, his other curled into your thigh. You turn into his touch and kiss his palm, muffling your heavy breathing as you do so. He leans back and watches as you bliss out.

“Man, if I’d’ve known you were this freaky from the start?” His voice is breathless. “Wouldn’t’ve let you leave Snowdin.” He thrusts into you a little harder and you moan, sudden and loud. “Woulda kept you in my bed and fucked you senseless.” He cups a hand over your mouth to muffle the whimpering sob you let out. “God, you’d look so good in my bed.” He says, sounding like an afterthought. You moan brokenly and wrap your arms around his neck.

Sans speeds up his thrusts, keeping them steady and hard. You’re quivering, right on the edge, unsure if you’ll be able to hold back. “Sans, I can’t… _Hhhhooohhhh_ fuck, Sans, slow down…” You twist your fingers up in the back of his sweater and tremble all over. You clench your thighs in a vain hope that it will stave off your impending release.

“Cum.” He whispers, close against your ear and with his permission you _do_ , sudden and hard. You feel wetter than ever, tightening up so much so that you can even better feel every inch of his cock. His breathing gets even harder and his thrusts slow as you come down. You feel fucked out and happy, so satisfied and weak at the knees. He barely gives you a moment to enjoy it.

Sans has to cover your mouth again at the shocked, loud half-scream you let out as he starts to fuck you in earnest. Your shirt has ridden back up in the back, brick digging into your skin and chafing. You’re so tight, so _sensitive_. He’s thrusting hard and fast, jolting you against the wall with every pulse of his hips. An endless stream of noises is leaving you now, and you’re so scared someone will hear you; or even worse, someone will _see_ you. You shouldn’t be getting _more_ turned on at the thought.

“So tight for me, _hhf_ , you’re so good sweetheart.” His breath is short and shallow, voice deep and throaty. You moan some kind of response into his hand. He removes it to dip between your legs and you bite your lip. It won’t nearly be enough, not with the way he’s rubbing his thumb against your clit with a purpose now. “Cum for me again, babe. One more time.” You wriggle against him, panting. His thrusts are getting more broken and he’s letting out little moans and grunts between them. You can’t deny him his wish.

You grind down against his dick and he moans along with you; his thumb rubs in circles on your clit and you sob out a moan, tears prickling at the edge of your vision. “Please, Sans, please cum with me, please, _please!_ ” You’re absolutely babbling, out of your mind with pleasure and lust and you shake through a second orgasm. He grins and pulls you against him, hands on your hips and thrusting hard and fast.

Oversensitive, tight, and slick, you squirm weakly against and away from him. It’s all too much and yet you want more and you let out a delighted moan when you feel his cock jerk inside you, cum hot and filling you up. The way he groans and sags against you is its own reward.

You both breathe for a few moments, the shadows and your position hiding his face. Everything feels sticky and too warm. You cup his jaw in both hands and turn him to look at you. Sans raises his eyes to meet yours and looks… sheepish, of all things.

“Oh yeah, I’m definitely staying.” You whisper, and kiss him softly.

Sans just grins.


End file.
